// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "cc/input/scroll_state.h"

#include <utility>

#include "cc/trees/layer_tree_impl.h"
#include "cc/trees/scroll_node.h"

namespace cc {

ScrollState::ScrollState(ScrollStateData data)
    : data_(data)
    , layer_tree_impl_(nullptr)
{
}

ScrollState::ScrollState(const ScrollState& other) = default;

ScrollState::~ScrollState() { }

void ScrollState::ConsumeDelta(double x, double y)
{
    data_.delta_x -= x;
    data_.delta_y -= y;

    if (x || y)
        data_.delta_consumed_for_scroll_sequence = true;
}

void ScrollState::DistributeToScrollChainDescendant()
{
    if (!scroll_chain_.empty()) {
        const ScrollNode* next = scroll_chain_.front();
        scroll_chain_.pop_front();
        layer_tree_impl_->LayerById(next->owning_layer_id)->DistributeScroll(this);
    }
}

} // namespace cc
